An Intersessional Working Group (IWG) was formed by the Eurobats’ Advisory Committee (Lithuania 2004) to investigate the impact on bat populations of the use of antiparasitic drugs (endectocides) for livestock, in conjunction with work being carried out under the Bern Convention. These drugs are used for the control of external and internal parasites of a wide range of domesticated farm animals. Concern has been raised that the drugs persist into the faeces of the livestock and affect the normal insect dung fauna which is an important element of the diet of a number of species of bat. 

The main agreed activities of the group were 

1) to establish current practices throughout Europe via a questionnaire, 

2) to carry out a literature review, 

3) to identify the bat species most likely to be affected by the use of these drugs, 

4) to identify any international initiatives or the presence of wider conservation 

concerns about the use of these drugs, 

5) to identify any future action that Eurobats should pursue regarding the effect 

on bats of the use of these drugs.